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LP12 makes front cover of Stereophile

Discussion in 'audio' started by Tony L, May 16, 2022.

  1. Mr Pig

    Mr Pig Trade: ^'- -'^

    I've heard differing versions of events. Living here you meet people who actually worked at Linn or knew Hamish but you know yourself that it's rare to get the truth from one side of the story.

    On the one hand you hear the standard 'Linn are bad and stole it' narrative. The other side is that Hamish was a bit erratic and difficult to deal with and wasn't paying for the decks he was ordering. Castle/Ivor got fed up with this and decided it would be better to just do it themselves. Unsold RD11 decks were sold as the LP12 and the rest is history.

    I'm not going to say where the truth is exactly, I wasn't there, but I do suspect it's in the middle somewhere. We know Linn can be pretty 'sharp' with their dealers and marketing but it's hard to argue with history. Linn did do a better job at developing and selling the turntable and Hamish Roberson drank himself to death. If Castle had simply continued to build turntables for Hamish do I think the deck would be what it is today? Absolutely not.
     
    Miss Ariel, AndyU and Mike1965 like this.
  2. Tony L

    Tony L Administrator

    There’s a very good comparison of the AR-XA and the TD-150 here on Analogue Dept. Mr Pig is right in that the platter mass of the AR is far lower than I recall. Regardless I’d still argue all original thinking was done between these two decks and the Sony TTS-3000 I link to above. All Linn did was bring it all together at a higher price-point and corresponding engineering quality (though I’d argue Linn’s pressed steel subchassis was inferior to the AR’s cast design). Even things like the motor azimuth adjustment came with the TD-150 in the mid-60s.
     
    John R and tenpercenter like this.
  3. Tony L

    Tony L Administrator

    Sony could likely have challenged Linn as the latter patented what was very clearly pre-existing technology. The Linn Wikipedia entry suggests their bearing design dates from 1971, so five full years after the remarkably similar Sony was a commercially available product. It would be interesting to see if there is anything similar before the Sony. It wouldn’t surprise me as it is a logical approach to the problem.
     
    John R, tpetsch and sonddek like this.
  4. sonddek

    sonddek Trade: SUPATRAC

    My point was legalistic. Did Sony patent it? If not, how would they attempt to stop others exploiting it?
     
  5. Martyn Miles

    Martyn Miles pfm Member

    To me, in the end, it’s how it sounds.
    My XA has a Denon MC cartridge fitted, very similar to the one fitted to my LP12.
    I get musical satisfaction from my AR.
    That’s what is important to me...
     
  6. guydarryl

    guydarryl pfm Member

    Many years ago I worked for ICI on PVC research. We used to read patents in order to get ideas for product development (very difficult to write a "watertight" patent).

    In PVC emulsion polymerisation we had a unique system which we didn't patent so as to block competitors from gaining inside information - if someone else had discovered the system and patented it, we had the documentation to be able to claim "prior knowledge" and thereby invalidate their new patent.
     
    Paul L, RJohan and Mr Pig like this.
  7. cre009

    cre009 pfm Member

    Yes Sony or Thorens could have challenged the bearing design and my expectation is that the Tiefenbrun's would have conceded without it ever going to a hearing.

    Hamish Robertson initially intended to challenge the patent based on prior use

    "Following publication of the Tiefenbrun patent in May 1975, an opposition was lodged by Fergus Fons Ltd and William James Robertson, better known as Hamish Robertson on various grounds eg that what it claimed as new, was in fact old keeping in mind what had been shown to the Harrogate Audio Festival in 1971. They also opposed on the grounds that the idea was 'lacking in inventive step' over what was already known to engineers. A further ground of opposition was that the invention had been 'obtained' from Hamish Robertson, that is to say was rightly the invention of Hamish Robertson and not Jack Tiefenbrun."

    The problem that Hamish Robertson had was that his own advertising claimed a unique point bearing following over a year of development.

    This would allow Jack Tiefenbrun to argue that his point bearing design was special and those by Thorens or Sony were just mundane ordinary point bearings.

    It would have been possible for him to attack the patent based on this but he would have had to argue against his own literature and also come up with an explanation why it would have been unreasonable for Jack Tiefenbrun to believe the literature was accurate. This would have destroyed his credibility so it appears he gave up on this when it came to the hearing.

    The Patent Officer was not satisfied that Jack Tiefenbrun had defined what was special but it appears this did not create any grounds to throw out the patent.

    It is clear from the patent coverage that the Ariston RD11 was based on a prototype turntable developed by Ivor at Castle. This would have been done with the help of Castle employees.

    Outside the hearing Ivor has named former Castle staff who helped him with the development. "The design benefited from the input of my late father who designed the patented single point bearing and from the key engineering staff at Castle Precision Engineering, my late father’s company, including John Cross, Bob Hamond, George Borthwick and the late Russell Christie and Edgar Clumpas who all enthusiastically helped me with this ‘lunchtime’ project, along with many other employees at Castle". This implies that the Tiefenbruns would have been able to call on many witnesses at the hearing if true.

    http://www.positive-feedback.com/pfbackissues/0706/Ivor.7n6.html

    Also elsewhere Ray Collins, a former Castle employee (and later Ariston Acoustics) not named by Ivor above told Nigel Pearson that he helped Ivor with the development which provides some independent corroboration that Ivor did the early development. "Ray used to do listening tests with Ivor. Ray said he couldn't hear the differences and would humour Ivor by saying he did".

    https://www.diyaudio.com/community/threads/sound-quality-vs-measurements.200865/page-777
     
  8. Tony L

    Tony L Administrator

    They couldn’t prevent others from using it, but I’d have thought they could get the patent thrown out. My guess is Sony just viewed it as such routine/bog-standard engineering that they didn’t even think about patenting it. As an example the step-pulley in a late MkI or MkII TD-124 has an almost identical single point bearing to the Linn main bearing but on a correspondingly smaller scale, and that’s an ancient design. Here’s an eBay listing with decent pictures. There really isn’t anything unique, big or clever about this type of bearing to my mind. I bet there is prior use going back centuries before Linn patented it.
     
  9. Mr Pig

    Mr Pig Trade: ^'- -'^

    I agree. Apart from the legal wranglings, I don't think it's very important at all. If you listen to an early Ariston with a captive ball it sounds very similar and just as good as an early LP12 and many other manufacturers have used ball bearings too. Maybe it's a little better but I think other aspects of the bearing design will be more important.

    Yeah but you could say that about a lot of things. Very few cars exhibit quantum leaps over their predecessors, they're all just incremental developments, but to dismiss this work as irrelevant is unfair. It still takes a lot of work to improve on a design.

    Also, building cutting edge products is not without risk, which is why car manufacturers tend to avoid it. Reliability matters too much to them. Tesla are a good example of what happens when you use too many new technologies. Impressive cars but not very good build quality and reliability.
     
    Miss Ariel likes this.
  10. John R

    John R pfm Member

    Early Linn main bearings do not look to be very high spec/ high quality components, unlike the later ones eg from the black liner pre Cirkus, through Circus era to their very well engineered Karousel.
     
    Miss Ariel likes this.
  11. rn82497

    rn82497 pfm Member

    In a word "yes". I'll ping you an e-mail
     
  12. Mr Pig

    Mr Pig Trade: ^'- -'^

    You could start a new thread, I'd quite like to hear about it? I've only used the Stack Tenor top-plate and sub-chassis but I'm impressed with them.
     
  13. sonddek

    sonddek Trade: SUPATRAC

    IANAL, but this was my legalistic point: as I understand it, there's not much point going round the world trying to get unassertable patents thrown out as there are too many of them. What you do is ignore them and sell your stuff. It's for the patent holder to bring a case, not the alleged patent infringer. If you've got good evidence you were selling the idea before the patent holder registered it, then you just carry on as if the patent didn't exist and wait for the patent holder to sue you, with or without justification. It does have relevance in the Robertson-Linn contretemps, because as I understand it, Robertson brought a case with inadequate evidence that he had published or sold the mechanism first, so the question of the validity of Linn's patent to stop other firms exploiting the design was not at stake. The only issue was: could Robertson invalidate it and assert his own exclusive right? It seems not. Please correct me if I'm wrong.
     
  14. Tony L

    Tony L Administrator

    Yes, that makes sense. It just kind of irks me that it is so obviously possible to patent long-existing technology designed by others, but I guess history is littered with that.
     
  15. sonddek

    sonddek Trade: SUPATRAC

    Yes, but the consolation is that a patent holder who brings and loses a patent case due to prior art has indulged in a painful waste of time and money.

    A friend in F1 told me that a household name auto firm brazenly infringed his firm's gear box patent, saying "sue us", because the cost to the holder and the tenacity in court of the infringer would mean any victory would be Pyrrhic.
     
  16. cre009

    cre009 pfm Member

    You can read the patent hearing articles here

    https://postimg.cc/image/rhott93yt/

    https://postimg.cc/image/7abe0ye79/

    https://postimg.cc/image/4g88nirgl/

    https://postimg.cc/image/e0rvae92t/

    The hearing officer made the following findings

    "He noted for instance Mr Robertson's evidence was shown in cross examination to be not always self consistent, and finally decided that the opponents (Fons and Robertson) had failed to prove their allegation that the bearing invention had rightfully been made by Robertson. In British Patent Law the onus of proof in such a serious ('obtaining') allegation is on the person who makes that allegation, and it is a very heavy burden of proof. In the Hearing Officer's view, Fons and Robertson had failed to discharge the onus of proof. To say that however, is a very long way from saying that I am satisfied that Mr Tiefenbrun was the inventor... Two matters have come to light in these preceedings which have caused me some disquiet

    The first matter that bothered the Hearing Officer was that there had been a sale by Linn of a deck which was stylistically similar to that which had been produced by Castle for Ariston (as the RD11) and that the sale had been without credit or reward to Hamish Robertson, even though it was admitted that the styling of the deck was indebted to Robertson. The Hearing Officer was also disturbed at the paucity of detailed information to be found in the patent on the exact nature of the bearing. Although as previously explained, the bearing was agreed to be the nub of the invention, the patent description deals with it in only very general terms. And as also previously explained, British Patent Law requires that the inventor gives the public adequate and full details of the invention."

    The Hearing Officer then came to a decision in favour of Fons and Hamish Robertson.

    "Despite the Hearing Officers reservation on such points and on the matter of who actually invented what, it was on the issue of prior publication and obviousness that he finally came down in favour of Robertson and Fons and against Tiefenbrun. The Hearing Officer accepted the Fons-Robertson argument that sufficient of the invention claimed in the Tiefenbrun patent had been disclosed to the public at Harrogate in 1971 (more than 6 months ahead of the date when Tiefenbrun filed his patent application) to make each and every claim of the patent invalid."

    The Tiefenbrun's lodged an appeal against this finding and the Appeals Judge (Mr. Justice Whitford) found in favour of the Tiefenbrun's. A summary was provided in a further article by Adrian Hope with the title "The Linn/Ariston/Robertson Affair (Part 2)" on page 53 of the July 1978 edition of Hi-Fi News & Record Review.

    "The Appeals judge agreed that the Patent Office had been right in refusing to accept Robertson's claim that the Linn bearing was his invention and not Tiefenbrun's. But the judge disagreed with the Patent Office on the crucial issue of whether or not the public demonstrations of the Ariston turntable and bearing at Harrogate in 1971 should invalidate the bearing patent subsequently filed by Tiefenbrun. There is in British Patent Law a provision (Section 50 of the Patent Act, 1949), which says that if an invention is published without the consent of the inventor it does not invalidate a subsequent patent application by the inventor. In other words, if the public demonstration of the Ariston turntable at Harrogate in 1971 took place without the blessing of Tiefenbrun it should not invalidate the patent application that Tiefenbrun filed in 1972".
     
  17. Dowser

    Dowser Learning to bodge again..

    And there you go… But we have all heard this before? Linn were bastards, but successfully proceeded to produce one of the worlds most longest living turntables, core to their success. Could have been different, but wasn’t.
     
  18. Tony L

    Tony L Administrator

    The Sugden Connoisseur Craftsmen III mentioned in the final piece is interesting, some pics here. That pushes a single point turntable main bearing design back to at least 1963!
     
  19. sonddek

    sonddek Trade: SUPATRAC

    It is amazing that any patent was granted at all. The Romans must have been using this.
     
  20. nobeone

    nobeone Total Member

    What have the Romans ever done for us?
     
    torstoi likes this.

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